Ken Seipel set up a Nativity scene last week in preparation for Friday and the start of Interlochen’s annual lights show.

Cameron Livesay made sure his green lights were twinkling as he hung them at his home.

George Slater strung lights for his aunt, an Interlochen resident. Friends and family pitch in to make sure the show goes on.

Around this time of year, Ralph Sobel keeps a concerned eye on his Porto Bello Court neighbors.

Some of those who live in Arlington’s Lake Interlochen neighborhood are getting older and, whether they like it or not, they sometimes need a little extra help during the holidays.

Any resident of Interlochen, a circuitous 100-acre west Arlington development, is likely to be involved in its famed over-the-top holiday light displays that attract visitors from far and wide. The Interlochen Christmas Lights event starts Friday night and continues through Dec. 25.

Decorating isn’t mandatory, but because they’re so caught up in the spirit, neighbors say, it doesn’t feel like work.

Sobel is concerned about those who can’t make it up the ladder easily anymore or can’t make it outside to decorate because of health problems.

So he and other neighbors, along with residents’ grandchildren and other family members, pitch in to keep the 30-year Arlington tradition burning bright.

“It’s something that has worried me a little,” said Sobel, who is president of the Lake Interlochen Homeowners Association. “Most people, when their kids grow up, they don’t want to pay the taxes or utilities on a bigger house and they move away. It’s not like that here.”

Even Interlochen’s original developer, Bob Findlay, now 91, still lives there.

Sobel said residents don’t want to scale back or give up on their displays, so they also help one another by lending spare yard decor.

The neighbors behind the elaborate holiday displays are a close-knit group who regularly get together for parties and social events year-round.

“We’re pretty close,” said Sobel’s wife, Alice, who is known for her immaculately outfitted bay windows that resemble New York City department store displays.

Jim Haskell stopped by on a recent afternoon to borrow Sobel’s ladder. The longtime Porto Bello Court resident said he gets a bit slower each year at outfitting his yard and house, but he counts on his grandson and his friends who live nearby.

“This is the friendliest neighborhood that I’ve ever lived in,” he said. “It’s phenomenal. I always say only two things could make me leave Porto Bello Court: a heart attack or an atomic bomb.”

Carole Findlay said she and Bob have lived in the same Porto Bello Court home for 36 years.

“I have a great support group on this street,” she said. “I can’t tell you how many people have lived here 30 years or more. Not everyone has this. I feel really well taken care of.”

Interlochen’s lazy trail of streets and cul-de-sacs are dotted with canals that reflect Christmas lights on the water, making it ideally suited for yard after yard of holiday illumination.

But the traffic that descends on the neighborhood can be overwhelming, even for those who are used to it. Police are needed to direct the heaviest weekend traffic.

Local benefactors including Allan Saxe, a philanthropist and University of Texas at Arlington professor, have again contributed money to fund traffic patrols.

Saxe doesn’t live in Interlochen but said the neighbors there make him feel as if he does. He said he’s honored to support what he called an Arlington institution.

“People actually help one another there. It’s like what a neighborhood was like 40 years ago,” he said. “There’s an old adage that says, ‘Fences make good neighbors.’ That’s not true in Interlochen. It’s a remarkable neighborhood.”

Come holiday time, there’s no home in the development that looks quite the same.

The one thing they all have in common is a willingness to go over-the-top. It’s not just the house or the lawn or the roof or the windows that gets decked out — it’s all of the above.

Some favor a blanket of all-white, blue or retro red and green lights strewn across rooflines and lawns.